:root {
  --color-background: #f6f7f9;
  --color-surface: #ffffff;
  --color-text: #202936;
  --color-muted: #5f6b7a;
  --color-accent: #3157a4;
  --color-border: #dfe3e8;
  --content-width: 960px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--color-text);
  background-color: var(--color-background);
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP", sans-serif;
  line-height: 1.7;
}

a {
  color: inherit;
}

.container {
  width: min(100% - 40px, var(--content-width));
  margin-inline: auto;
}

.site-header {
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  gap: 24px;
}

.site-title {
  color: var(--color-accent);
  font-size: 1.25rem;
  font-weight: 700;
  text-decoration: none;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-list a {
  display: block;
  padding-block: 8px;
  color: var(--color-muted);
  font-weight: 600;
  text-decoration: none;
}

.nav-list a:hover,
.nav-list a:focus-visible {
  color: var(--color-accent);
}

.intro {
  padding-block: 72px;
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.intro-label {
  margin: 0 0 8px;
  color: var(--color-accent);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.intro h1 {
  margin: 0;
  font-size: clamp(2rem, 6vw, 3rem);
  line-height: 1.3;
}

.intro p:last-child {
  max-width: 640px;
  margin: 16px 0 0;
  color: var(--color-muted);
}

.section-list {
  display: grid;
  gap: 24px;
  padding-block: 56px;
}

.content-section {
  padding: 32px;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  overflow-wrap: break-word;
  scroll-margin-top: 24px;
}

.content-section h2 {
  margin: 0 0 8px;
  font-size: 1.5rem;
}

.content-section p {
  margin: 0;
  color: var(--color-muted);
}

.about-section .about-summary {
  max-width: 760px;
  margin-top: 16px;
  color: var(--color-text);
}

.about-details {
  display: grid;
  gap: 32px;
  margin-top: 32px;
  padding-top: 32px;
  border-top: 1px solid var(--color-border);
}

.about-block h3 {
  margin: 0 0 12px;
  color: var(--color-accent);
  font-size: 1.125rem;
}

.focus-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0;
  padding: 0;
  list-style: none;
}

.focus-list li {
  padding: 6px 12px;
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-weight: 600;
}

.goal-list {
  display: grid;
  gap: 8px;
  margin: 16px 0;
  padding-left: 1.5rem;
}

.goal-list li::marker {
  color: var(--color-accent);
}

.projects-section .projects-introduction {
  max-width: 760px;
  margin-top: 16px;
}

.project-list {
  display: grid;
  gap: 24px;
  margin-top: 24px;
}

.project-card {
  padding: 24px;
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: 6px;
}

.project-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
}

.project-card .project-category {
  margin-bottom: 4px;
  color: var(--color-accent);
  font-size: 0.875rem;
  font-weight: 700;
}

.project-card h3 {
  margin: 0;
  font-size: 1.375rem;
}

.project-status {
  flex-shrink: 0;
  padding: 4px 10px;
  color: var(--color-accent);
  background-color: var(--color-surface);
  border: 1px solid var(--color-accent);
  border-radius: 999px;
  font-size: 0.8125rem;
  font-weight: 700;
}

.project-card .project-summary {
  max-width: 760px;
  margin-top: 20px;
}

.project-details {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

.project-detail h4 {
  margin: 0 0 12px;
  font-size: 1rem;
}

.technology-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.technology-list li {
  padding: 6px 12px;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-weight: 600;
}

.project-feature-list {
  display: grid;
  gap: 6px;
  margin: 0;
  padding-left: 1.5rem;
}

.project-feature-list li::marker {
  color: var(--color-accent);
}

.project-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--color-border);
  font-size: 0.875rem;
}

.project-links strong {
  color: var(--color-text);
}

.skills-section .skills-introduction {
  max-width: 760px;
  margin-top: 16px;
}

.skills-section .skills-legend {
  margin-top: 12px;
  font-size: 0.875rem;
}

.skills-legend strong {
  color: var(--color-text);
}

.skill-groups {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  column-gap: 32px;
  margin-top: 28px;
}

.skill-group {
  padding-block: 24px;
  border-top: 1px solid var(--color-border);
}

.skill-group h3,
.learning-plan h3 {
  margin: 0 0 12px;
  color: var(--color-accent);
  font-size: 1.125rem;
}

.skill-status-list,
.learning-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.skill-status-list li,
.learning-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-block: 8px;
  border-bottom: 1px solid var(--color-border);
}

.skill-name {
  font-weight: 600;
}

.skill-state {
  display: inline-block;
  flex-shrink: 0;
  padding: 2px 8px;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  line-height: 1.5;
}

.skill-state.is-using {
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.skill-state.is-learning {
  color: var(--color-text);
}

.skill-state.is-next {
  color: var(--color-muted);
  border-style: dashed;
}

.skill-group .skill-description {
  margin-top: 16px;
  font-size: 0.9375rem;
}

.skill-topic-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.skill-topic-list li {
  padding: 5px 10px;
  background-color: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-size: 0.875rem;
}

.learning-plan {
  margin-top: 8px;
  padding: 24px;
  background-color: var(--color-background);
  border-left: 4px solid var(--color-accent);
  border-radius: 4px;
}

.learning-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  column-gap: 24px;
  margin-top: 16px;
}

.site-footer {
  padding-block: 24px;
  color: var(--color-muted);
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
  text-align: center;
}

@media (max-width: 720px) {
  .content-section {
    padding: 28px;
  }

  .project-details,
  .skill-groups,
  .learning-list {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .container {
    width: min(100% - 32px, var(--content-width));
  }

  .header-inner {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    gap: 4px;
    padding-block: 12px;
  }

  .nav-list {
    gap: 16px;
  }

  .intro {
    padding-block: 40px;
  }

  .section-list {
    gap: 20px;
    padding-block: 32px;
  }

  .content-section {
    padding: 20px;
  }

  .about-details {
    gap: 24px;
    margin-top: 24px;
    padding-top: 24px;
  }

  .project-card {
    padding: 16px;
  }

  .project-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }

  .project-details {
    gap: 20px;
    margin-top: 20px;
    padding-top: 20px;
  }

  .project-links {
    gap: 8px 16px;
    margin-top: 20px;
    padding-top: 16px;
  }

  .skill-groups {
    margin-top: 24px;
  }

  .learning-plan {
    padding: 16px;
  }

  .learning-list li {
    align-items: flex-start;
  }
}